Conventionally, pain caused by rheumatic diseases and locomotorium diseases has been treated with nonsteroidal antiinflammatory, local anesthetic and antispasmodic which are generally referred to as analgesics in a wide sense, and vasoconstriction, vasodilator and muscular relaxant having other actions as well, which may be used in combination. This treatment using plural medicaments is based on the development mechanisms of pain, and the mechanism of action of medicaments. For example, nonsteroidal antiinflammatory exhibits etiotropic effects by inhibiting synthesis of the pain-producing substance prostaglandins, while local anesthetic exhibits symptomatic effects by blocking transmission of neurostimulation from local pain source to the center, and the combination of these medicaments aims at synergistic effects afforded by their different actions displayed at different sites. An exemplary of the medicaments formulated for achieving such synergistic effects is Neo Vitacain injection.RTM. (VITACAIN PHARMACEUTICAL CO., LTD., Japan), which is a local injection containing dibucaine hydrochloride, sodium salicylate, and calcium bromide as active ingredients and having a formulation shown below, and is markedly effective as an analgesic for use in a pain treatment of head neuralgia, muscle pain, rheumatism, low backache, etc. Usefulness of Neo Vitacain injections.RTM. and its analogous therapeutic compositions for the treatment of pain will be greatly enhanced if the effect thereof could be improved.
______________________________________ Formulation of Neo Vitacain injection .RTM. (100 ml): ______________________________________ Dibucaine hydrochloride 100 mg Sodium salicylate 300 mg Calcium bromide 200 mg Thiamine hydrochloride 200 mg Pyridoxin hydrochloride 100 mg Calcium pantothenate 100 mg ______________________________________